JPH0694022B2 - Control method in sealing agent application device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a control method in a sealant coating device.

2. Description of the Related Art In the manufacture of automobiles, for example, as disclosed in Japanese Patent Application Laid-Open No. 55-81759, a viscous resin is used for the purpose of preventing intrusion of water, wind, etc. at the joints of the constituent members of the automobile body. Applying sealant. At the time of applying the sealing agent, recently, a sealing agent applying apparatus in which an arm of an industrial robot is assembled with an applying gun having a discharge pump is used.

Problems to be Solved by the Invention In a corner part of a work in which the moving direction of the coating gun changes, for example, from the X direction to the Y direction, the moving speed of the arm of the industrial robot becomes slow, so that the coating position is changed depending on the coating position. Although the rotation speed of the discharge pump is programmed in advance and open control is performed so that the coating amount is always constant, the coating width of the sealing agent applied to the workpiece is detected,
The difference between the detected coating width and the preset reference coating width is obtained, and the close control for making the difference zero is not performed.

Here, regarding the sealing agent, it has the property that the viscosity changes according to the ambient temperature, and even when the rotation speed of the discharge pump is controlled at a constant speed in the linear portion where the coating gun moves at a constant speed. The viscosity of the sealing agent changes depending on the ambient temperature, the discharge amount changes, and the discharge amount also changes due to the pressure change in the supply source, which causes variations in the coating properties such as the coating width. For this reason, an inspection is performed after coating, and for example, a portion where the coating width is insufficient is manually replenished with a sealing agent, or a sealing agent at a portion where the coating amount is too large is removed. It takes time.

Therefore, it is an object of the present invention to provide a method for controlling a sealing agent coating device, which can control the coating width and the coating position of the sealing agent in a good close condition to improve workability.

Means for Solving Problems A control method in a sealing agent applying apparatus according to the present invention is to apply a sealing agent to a predetermined position from an end portion of a work by an application gun equipped with a discharge pump assembled to an arm of an industrial robot. In a sealing agent applying device adapted to continuously apply a bead shape to a work with an application width of, the application width of the sealing agent applied to the work is made to follow the application property detection by a visual sensor to the movement of the application gun. In addition to detecting, the distance from the end of the work to the sealing agent is detected as the coating position dimension of the sealing agent, and the detected coating width and coating position dimension are set in real time with the preset reference coating width and reference coating position dimension. By comparison, when it is judged that the coating width is wider than the standard coating width, or when it is larger than the standard coating position dimension. When it is determined that the application position size is small, the discharge amount of the delivery pump is reduced, while when it is determined that the application width is narrower than the reference application width, or when the application position size is greater than the reference application position size. When the determination is made, the discharge amount of the discharge pump is increased, and when the coating width is wider than the upper limit value of the reference coating width and narrower than the lower limit value of the reference coating width, abnormal processing is performed. .

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

1 and 2 are views showing an embodiment of the present invention, and particularly FIG. 1 shows the whole sealing agent applying apparatus. In FIG. 1, the sealant coating device is composed of an arm 2 of a teaching playback type industrial robot 1 and a coating gun 4 mounted on the tip of the arm 2 and equipped with a discharge pump 3. The coating gun 4 is adapted to continuously apply the sealing agent S to the work W in a bead shape. That is, according to a command from the control unit 5 of the industrial robot 1, the arm 2 is operated for playback and the sealing agent S is supplied from the supply source 6 to the discharge pump 3.

Note that FIG. 2 shows an example of an outer panel of an opening / closing body such as a door panel as the work W, and is attached to the peripheral portion of the work (outer panel) W to be hemmed with an inner panel (not shown) in a later step. The hemming flange portion F is formed in advance, and the sealing agent S is applied in a bead shape to the portion to be hemmed.

Here, the coating property detecting means 7 is attached to the arm 2. The coating property detecting means 7 includes a light source 9 attached to the coating gun 4 via a bracket 8 and an image pickup device 10 as a visual sensor, and is coated on the work W so as to follow the coating gun 4. The coating width d and the coating position dimension t of the sealing agent S are detected.

As shown in FIG. 2, the image pickup device 10 includes an image pickup lens 11,
And a one-dimensional image sensor 12 arranged at the image forming position thereof, and the one-dimensional image sensor 12 through the imaging lens 11.
The image captured in (3) is output by the information processing unit 13 as a binarized video signal Q.

Reference numeral 14 in FIG. 1 is a coating amount control means connected to the coating property detecting means 7. A video signal Q is inputted to the coating amount control means 14, and a standard coating width such as a coating width d of the sealing agent S and a coating position dimension t, a standard coating position dimension and the like are programmed and set in advance. . The coating position dimension t here is the distance dimension from the hemming flange portion F at the end portion of the work W to the bead-shaped sealing agent S as shown in FIG. Then, the coating amount control means 7
Compares the application width d or the application position dimension t detected as the video signal Q with a preset reference application width or reference application position dimension, and feeds back the difference to a servo amplifier (not shown) of the discharge pump 3. The discharge amount of the discharge pump 3, specifically, the number of revolutions is controlled so that the difference becomes zero.

Further, the coating amount control means 14 is adapted to generate a warning signal K when the difference is below a lower limit value or above an upper limit value in a required range. This warning signal K is
It is sent to the control unit 5 of the industrial robot 1 and the alarm means 15 such as a lamp or a buzzer to automatically stop the driving of the industrial robot 1 or notify the operator of a coating abnormality.

That is, the operator causes the industrial robot 1 to learn a required coating locus by teaching work, and information such as the coating width d and the coating position dimension t corresponding to the coating locus and the reference coating width and the reference coating position dimension. Is stored in a memory (not shown) of the coating amount control means 14. As a result, the sealing agent S is applied to the work W from the application gun 4 by operating the entire system under the control of the controller 5 of the industrial robot 1.

At this time, the imaging device 10 of the coating property detecting means 7 detects the coating width d and the coating position dimension t of the sealing agent S coated by the coating gun 4 based on the difference in the amount of light received by the reflected light from the light source 9, The binarized video signal Q is sent to the coating amount control means 14. Then, the coating amount control means 14 makes the discharge pump 3 such that the difference between the coating width d or the coating position dimension t by the coating gun 4 and the preset reference coating width or the standard coating position dimension becomes zero in real time. Feedback control the number of revolutions.

As a result, even if the viscosity of the sealing agent S becomes low or high due to the change of the atmospheric temperature during the coating, or the pressure of the supply source 6 changes, the coating width d by the coating gun 4 is It becomes a suitable fixed amount at the position, and the coating width d is not too wide or too narrow,
The sealing agent S is applied with a required reference coating width (in this case, the dimensions of the coating width d that are too wide or too narrow indicate variations with respect to the reference setting width,
Both are within the allowable range, so they do not become defective products, rather, they are set to values that prevent them from falling outside the allowable range).

More specifically, the detected coating width d is compared with a preset reference coating width, and when the coating width d is wider than the reference coating width, the rotation speed of the discharge pump 3 is decreased, and conversely, the coating width d.
Is smaller than the reference coating width, the rotation speed of the discharge pump 3 is increased. Similarly, the detected application position dimension t is compared with the reference application position dimension, and when the application position dimension t is smaller than the reference application position dimension, the rotation speed of the discharge pump 3 is decreased, and conversely, the application position dimension t is When it is larger than the standard application position dimension, the rotation speed of the discharge pump 3 is increased.

As described above, by using the coating position dimension t as a parameter of the coating amount control means 14, it is possible to position-correct the coating position dimensional error due to the manufacturing error and the positioning error within the tolerance of the work W. In other words, if the coating position dimension t becomes large or small and greatly varies, the position of the sealing agent S may deviate from the hemming joint portion between the outer panel and the inner panel, resulting in poor sealing of the hemming joint portion. However, as described above, the position of the sealing agent S is displaced by increasing or decreasing the rotational speed of the discharge pump 3 and thus the discharge amount according to the difference between the coating position dimension t of the sealing agent S and the reference coating position dimension. Is supplemented with the amount of the sealing agent S, and the hemming bond is reliably sealed.

On the other hand, as the sealing agent is insufficient in the supply source 6,
Supply of the sealing agent S to the discharge pump 3 becomes insufficient, and the coating width d is less than or equal to the required lower limit of the reference coating width, or conversely, the ambient temperature and the supply pressure are too high, and the sealing agent S is excessively supplied. When the coating width d exceeds the upper limit of the required reference coating width, the coating amount control means 14 outputs a warning signal K.
Is output to the control unit 5 and the alarm means 15 of the industrial robot 1 to stop the industrial robot 1 and inform the operator of the abnormality.

As described above, according to the present invention, during the application of the sealing agent, the application width and the application position dimension of the sealing agent applied to the work are detected, and the detected application width and application position dimension are set in advance. When comparing with the set reference coating width and reference coating position dimension in real time, when it is determined that the coating width is wider than the reference coating width or when it is determined that the coating position dimension is smaller than the reference coating position dimension If the discharge width of the discharge pump is reduced and it is determined that the coating width is narrower than the reference coating width, or if the coating position dimension is larger than the reference coating position dimension, the discharge amount of the discharge pump is reduced. If the coating width is wider than the upper limit of the standard coating width or narrower than the lower limit of the standard coating width, abnormal processing will be performed. The application position and the application position are always closed and controlled in a good state, and the work that was conventionally divided into three steps of application, inspection, and repair can be performed in one step. Moreover, when the application width becomes abnormal, it is abnormally processed. There is a new effect that workability is also improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the entire sealing agent coating device showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the relationship between the structure of coating property detecting means and the binary signal waveform thereof. 1 ... Industrial robot, 2 ... Arm, 3 ... Discharge pump, 4 ... Coating gun, 7 ... Coating property detecting means, 10 ...
Imaging device as a visual sensor, 14 ... Coating amount control means,
W: Work, S: Sealant.

Claims (1)

[Claims] 1. A coating gun equipped with a discharge pump assembled to an arm of an industrial robot so that a sealing agent is continuously applied to a work from an end of the work to a predetermined position with a predetermined coating width in a bead shape. In the sealing agent application device, the application property detection by the visual sensor is made to follow the movement of the application gun to detect the application width of the sealing agent applied to the work and the distance from the end of the work to the sealing agent. It is detected as the application position dimension of the sealing agent, and the detected application width and application position dimension are compared in real time with the preset reference application width and reference application position dimension, and it is determined that the application width is wider than the reference application width. If it is, or if it is determined that the application position size is smaller than the reference application position size, the discharge amount of the discharge pump is reduced. On the other hand, when it is determined that the application width is narrower than the reference application width or the application position dimension is larger than the reference application position dimension, the delivery amount of the delivery pump is increased. A method for controlling a sealing agent coating apparatus, wherein abnormal treatment is performed when is larger than the upper limit of the reference coating width and narrower than the lower limit of the reference coating width.